Aston Villa manager Martin O'Neill has warned his players Rapid Vienna will be no pushovers as the midlands club look to book their place in the group stages of the Europa League.

O'Neill is aware Vienna overcame Liverpool in a pre-season friendly ahead of tonight's first leg away to the Austrian side and is braced for "an extremely difficult test."

The former Celtic boss is set to make changes from the side beaten by Wigan but promises to field a strong line-up.

O'Neill said: "The game against Vienna is very, very important for us. I would love to play in the group stages. That would be important again for the development of the younger players in the squad - and the senior ones too.

"We will be striving very hard indeed to get through. Vienna beat Liverpool in pre-season - it will be an extremely difficult tie.

"We've had them watched every single time since we've known the draw. They're a really fine footballing side, excellent with the ball and with enough ability to cause us lots of problems going forward.

"Honestly, it will be tough for us, no doubt at all about it."

O'Neill added: "I will change the side a little bit but we will still be going very strongly with the players that we have available.

"I think it would be fair to say that there were easier teams in the group, but you have to accept it and get on with it.

"It's a test at this particular stage of the season. We came through a couple of those last year, like the game against Litex Lovech, and I think it will be every bit as severe as that."

It will be Villa's first taste of action in the competition since O'Neill upset a section of fans by fielding a shadow squad in the last-32 game away to CSKA Moscow in March.

But O'Neill stands by his decision even though Villa endured an end of season fade-out in the Barclays Premier League after their European exit.

He said: "For me, so much has been said about it, that it's mind-blowing. It really is mind-blowing that people are looking to that to explain what happened at the end of last season.

"It got out of proportion. People started saying that our whole season faded because of it, when in actual fact it was how we were trying to keep the season alive by utilising the players in the best way."

O'Neill, meanwhile, is believed to be lining up a bid for West Ham central defender Matthew Upson, who is rated at more than £10 million by the London club.

The Northern Irishman is desperate to strengthen the middle of his defence after skipper Martin Laursen was forced to retire through injury.

O'Neill also allowed Zat Knight to join Bolton which leaves him with only Carlos Cuellar and Curtis Davies as experienced centre-backs.

But he is understood to be keen on bringing in England squad regular Upson who previously played for Villa's local rivals Birmingham before moving to Upton Park during the January 2007 transfer window.